The Stars Will Disappear Forever
Our view of the universe has an expiration date.
What are Stars actually?
We look at the sky at night and see all the countless twinkling stars but most of us do not know that they are actually Suns of another solar systems which far far away from us. The stars that is nearest to us is what we call the Sun. These stars are basically giant spheres of gas and plasma held together by the insanely strong gravity (strength of the gravity depends on Mass and Distance!). We can fit around 1,300,000 Earths inside the Sun so you can guess how gigantic the Sun is and that explains its insanely strong gravity, that not just pulls its own core together but also the entire solar system exists because of our dear Sun. There are a lot of other interesting facts about the Sun or stars, but let's not get lost into the universe just yet!
Apologies for the cognitive overload but I couldn't hold myself back to drop in another mind boggling fact. There are around 400 billion stars in our galaxy, but the number becomes crazy when we look at the entire observable universe, which boasts around 1 septillion stars, which is 1,000,000,000,000,000,000,000,000 stars!
The Journey of Light
The light from the Sun takes 8 minutes and 20 seconds to reach Earth. So if you are outside and you are feeling the warmth of the sunlight, that exact light particle (or photon) started its journey around 8 mins ago, and finally reached you! Let's do some basic math to understand this. If you remember the classic speed, distance and time formula from the school
$$ Distance = Speed \times Time $$
Let me fill in the data you need to calculate the time for the light from the Sun to reach Earth. The Sun is around 150 million kilometers away from us and the speed of light (the fastest thing in the entire universe!) is roughly 300,000 kilometers per SECOND!
$$ Time = \frac{150,000,000 ; km} {300,000 ; km/s} \implies 500 ; seconds ; $$
That's about 8 minutes 20 second for ya! If you think this is a surprising, hold on... let me remind you that the sun is the closest star to us. The second closest star is Proxima Centauri which is 4.24 light years away from us or roughly 40 trillion kilometers away. A light year is basically the distance travelled by light (the absolute fastest thing in the universe) in a year, which is around 9.46 trillion kilometers, or thanks to google exactly 9,460,730,472,580 kilometers.
if a new life emerges, they can see only the curretn area and never know that there exist other galaxies! they will not even know about universe ! maybe thats what happened to us! that our observable universe is just a small galaxy and others are so far away!